the aim of this article is to extend the study of the lorentz transformation of order (m,n) from m=1 and n>=1 to all m,n>=1, obtaining algebraic structures called a bi-gyrogroup and a bi-gyrovector space. a bi-gyrogroup is a gyrogroup each gyration of which is a pair of a left gyration and a right gyration. a bi-gyrovector space is constructed from a bi-gyrocommutative bi-gyrogroup that admits ...

While you have probably used tensors of rank 1, i.e vectors, in special relativity, relativity is most efficiently expressed in terms of tensor algebra. General relativity, however, requires tensor algebra in a general curvilinear coordinate system. Before discussing special relativity, it will be useful to introduce some of the mathematics of differential forms in a general curvilinear set of ...

The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union will preserve an independent reality. H Minkowski (1908).

We reformulate Special Relativity by a quaternionic algebra on reals. Using real linear quaternions, we show that previous difficulties, concerning the appropriate transformations on the 3 + 1 space-time, may be overcome. This implies that a complexified quaternionic version of Special Relativity is a choice and not a necessity. a) e-mail: [email protected]

A special relativity based on the de Sitter group is introduced. Like ordinary special relativity, it retains the quotient character of spacetime, and consequently a notion of homogeneity. This means that the underlying spacetime will be a de Sitter spacetime, the quotient space between de Sitter and the Lorentz groups. Since the local symmetry will also be given by the de Sitter group, each ta...